CCIE RSv5 Workbook Full Scale Lab 1 Now Available
Full Scale Lab 1 has been added to the CCIE Routing & Switching v5 Workbook. More Foundation, Troubleshooting, and Full Scale Labs will be coming soon, including additional updates before the end of the weekend. I will post more information about additional content and its release schedule shortly.
This lab uses a 20 router topology which will be available through our rack rental system shortly. In the meantime if you have your own lab built on CSR1000v, IOU/IOL, etc. the initial configs are available to download on the lab 1 tasks page. For technical discussion of this lab, please visit the Full Scale Labs section of our Online Community here.
Who Uses the 55:4e:20 MAC OUI?
I set up a new secondary ISC DHCP server yesterday, as an interim solution while I get round to fixing a dead server. The easiest short term fix was to spin up a VM and install DHCP there. As I … Continue reading
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Renesys Team Launches Dyn Research
Welcome to the new Dyn Research Blog! We’re certainly glad you’re here, and we hope you like the snazzy new look.
Since the Renesys team joined Dyn in May, the number one question we’ve received is “will you keep publishing the blog?” The answer is yes, absolutely, and we hope to bring you some diverse perspectives on Internet performance from other members of the Dyn technical team as well. Please do let us know what you think of the new Dyn Research Blog, and feel free to suggest topics you’d like us to cover.
A moment for reflection
Looking back over the eight years that we’ve been publishing our observations about Internet structure and operations, I’m struck mostly by how you, our audience, have evolved and grown. In the early days, news about Internet infrastructure appealed to a pretty narrow group of readers within the network operations community. We never had to buy beer at conferences like NANOG, but the rest of the world was more or less content to ignore the dirty details of IPv6, peering and depeering, Net Neutrality, and the evolution of the IP wholesale transit industry.
Plexxi Pulse—HadoopWorld 2014: Is your network ready for Big Data?
We are two short weeks away from HadoopWorld, one of the world’s largest Big Data conferences. October 15—17 our team will be in in New York City to demo our Big Data fabric and answer questions about preparing networks for Big Data. Stop by booth 552 to catch up with our team and pick up a pair of Plexxi Socks. We look forward to seeing you there.
In this week’s PlexxiTube of the week, Dan Backman describes how Plexxi manages load balancing in Big Data networks.
Check out what we’ve been up to on social media this week. Have a great weekend!
The post Plexxi Pulse—HadoopWorld 2014: Is your network ready for Big Data? appeared first on Plexxi.
IPv6 Adoption in the UK
One of my biggest annoyances for a while has been the lack of interest in IPv6 in the UK. There just isn’t a thirst for it. I’m pretty convinced it’s down to lack of sales support by out coin operated fraternity of technology touting army of salesmen (and women). Justifications like “IPv4 is running out” and “IPv6 when wielded correctly gives us huge growth potential” just isn’t enough to convince anyone that it’s here and is ready for adoption in enterprises nationally. The commoditisation of last mile circuits and consumer grade connectivity has also driven down profit and therefore as these businesses run with tightly controlled finances, the ability to invest in additional functionality with no perceivable gain is frowned upon somewhat. So, a quote that I thumbed in to Twitter was “Would you expect sparkling vitamin water to come out of the same taps as your current still cold feed? Who would pay £1 a month more?”. The answer to this somewhat pointless frustrated question is probably not of any value to anyone barring technologists who get it. Of course you wouldn’t get it out of the same tap! Whilst it would be delivered from the same set Continue reading
Network Automation Tools with Jason Edelman on Sofware Gone Wild
The stars have finally aligned, and after months of scheduling Jason and myself found time to chat about network automation tools and all the other exciting things Jason is doing (and blogging about).
We started with easy topics:
Read more ...Arista vEOS on GNS3
EOS (Extensible Operating System) is Linux-based network operating system developed by Arista Networks that runs on all Arista switches. Virtual EOS (vEOS) is single image and can be run in a virtual machine. The article describes how to set up vEOS virtual machine and connects it to GNS3 in order to test EOS functionality.
Host Requirements
Linux x86-64
Qemu or VirtualBox installed
Virtual Machine Requirements
1024 MB RAM
IDE CD-ROM drive with mounted Aboot-veos-serial-2.0.8.iso
2GB flash IDE disk - vEOS-4.14.2F.vmdk
NICs e1000 type
1. Download Bootloader and Virtual EOS
Clik the link to create a new account. The guest account (when no corporate email is used for registration e.g. gmail.com) is sufficient to download vEOS software. Click the link and login with the credentials you entered during the registration. You have to accept License Agreement in order to download vEOS software.
Download the bootloader and a virtual disk:
Aboot-veos-serial-2.0.8.iso
vEOS-4.14.2F.vmdk
2. Arista Switch First Boot on Qemu
Use Qemu to boot Arista switch virtual machine for the first time.
$ /usr/local/bin/qemu-system-x86_64 -m 1024 -enable-kvm -cdrom ./Aboot-veos-serial-2.0.8.iso -boot d vEOS-4.14.2F.vmdk -serial telnet::3355,server,nowait
Connect to the Continue reading
Route leak incident on October 2, 2014
Today, CloudFlare suffered downtime which caused customers’ sites to be inaccessible in certain parts of the world. We take the availability of our customers’ web properties very seriously. Incidents like this get the absolute highest priority, attention, and follow up. The pain felt by our customers is also felt deeply by the CloudFlare team in London and San Francisco.
This downtime was the result of a BGP route leak by Internexa, an ISP in Latin America. Internexa accidentally directed large amounts of traffic destined for CloudFlare data centers around the world to a single data center in Medellín, Colombia. At the same time Internexa also leaked routes belonging to Telecom Argentina causing disruption in Argentina. This was the result of Internexa announcing via BGP that their network, instead of ours, handled traffic for CloudFlare. This miscommunication caused a flood of traffic to quickly overwhelm the data center in Medellín. The incident lasted 49 minutes, from 15:08UTC to 15:57UTC.
The exact impact of the route leak to our customers’ visitors depended on the geography of the Internet. Traffic to CloudFlare’s customers sites dropped by 50% in North America and 12% in Europe. The impact on our network in Asia was isolated Continue reading
Meet the new ISR Series – ISR 4000 running IOS-XE
In June of 2013 Cisco released the newest member of the ISR family, the ISR4451-X router (Cisco – blog post). At that time it was the only model in the ISR44xx line, but today it now has some new siblings. Today, October 2, 2014, Cisco has introduced some companious, namely the ISR 4321, 4331, 4351, and 4431. The […]Cables, Transceivers and 10GBASE-T
In the past few weeks at Plexxi we spend probably an unreasonable amount of time talking about, discussing and even arguing over ethernet cables and connectors. As mundane as it may sound, the options, variations, restrictions and cost variations of something that is usually an afterthought is mind boggling. And as a buyer of ethernet networks, you have probably felt that the choices you make will significantly change the price you pay for the total solution.
During our quarterly Product Management get together, my colleague Andre Viera took 25GbE as a trigger to walk the rest of the team through all the variations of cables and transceivers. As a vendor it is a rather complicated topic and as a customer I can only imagine how the choices may put you in a bad mood.
Most of today’s 10GbE switches ship with SFP+ cages and a handful of QSFP cages. Now comes the hard part. What do I plug into these cages? There are lots of choices all with their own pros and cons.
Direct Attach Cable
The cheapest solution is a Direct Attach Cable or DAC. These are copper based cables that have SFP+ transceivers molded onto the cable. It Continue reading
Cisco Expressway Setup
I am currently working on a Cisco Jabber project and my customer main requirement is that every users must be able to place calls in an easy way regardless from their location. Since the BYOD and Mobility are the trends I recommended the Cisco Expressway product line. I won’t go deep on how the expressway is […]Can I Be Brutally Honest?
There are several reasons I love being on the road. One of them is the sense of accomplishment I get from doing a particular job in a set amount of time. There is a defined period in which I will be on site with a client to do a job, or a set number of days I will be sitting in training. The light is always at the end of the tunnel. I find that when I am involved in projects around where I live, that they tend to drag on. Time is always important, but not as important as when I am on the road.
Another reason I love being on the road is the fact that I get to interact with a number of my fellow IT professionals on their home turf. I love talking to them about their networks and seeing how they solve the particular issues of their business with technology. I also love to help them improve their networks when needed. Depending on the engagement length, a good working relationship may develop to the point where you seek each other out for conversation or shared meals when you are in the same general vicinity. In Continue reading
Bufferbloat Killed my HTTP Session… or not?
Every now and then I get an email from a subscriber having video download problems. Most of the time the problem auto-magically disappears (and there’s no indication of packet loss or ridiculous latency in traceroute printout), but a few days ago Henry Moats managed to consistently reproduce the problem and sent me exactly what I needed: a pcap file.
TL&DR summary: you have to know a lot about application-level protocols, application servers and operating systems to troubleshoot networking problems.
Read more ...Universal SSL: How It Scales
On Monday, we announced Universal SSL, enabling HTTPS for all websites using CloudFlare’s Free plan. Universal SSL represents a massive increase in the number of sites we serve over HTTPS—from tens of thousands, to millions. People have asked us, both in comments and in person, how our servers handle this extra load. The answer, in a nutshell, is this: we found that with the right hardware, software, and configuration, the cost of SSL on web servers can be reduced to almost nothing.
Modern Hardware
CloudFlare’s entire infrastructure is built on modern commodity hardware. Specifically, our web servers are running on CPUs manufactured by Intel that were designed with cryptography in mind.
All Intel CPUs based on the Westmere CPU microarchitecture (introduced in 2010) and later have specialized cryptographic instructions. Important for CloudFlare’s Universal SSL rollout are the AES-NI instructions which speed up the Advanced Encryption Standard (AES) algorithm. There’s also a set of instructions called Carry-less Multiplication (CLMUL) that computes mathematical operations binary finite fields. CLMUL can be used to speed up AES in Galois Counter-mode (GCM): our preferred mode of encryption due to its resistance against recent attacks like BEAST.
As we described in our primer on TLS Continue reading
Traveling Light – 15 Things in an Engineer’s Bag (including the bag)
My day job involves traveling around northern Europe and occasionally further afield. I often get little notice of where I’m going, or how long I’m going for. This makes for a lot of trudging along train platforms and across departure lounges. Hauling too much stuff around is guaranteed to ruin my day. Traveling light becomes a necessity, […]
Author information
The post Traveling Light – 15 Things in an Engineer’s Bag (including the bag) appeared first on Packet Pushers Podcast and was written by Glen Kemp.
Interop Debate – What-to-Study 2-minute Drill
We’re holding the Interop debate today about traditional certifications versus studying SDN. During the debate, we expect to discus the specific topics we should be studying to learn SDN. And we each get roughly two minutes each, so the answer doesn’t easily fit. This post is here so I can point people at the show here, since they might not be able to furiously write it all down.
I will circle back to this topic following the show.
Prerequisites
- CCNA + CCNP R/S
- CCNA + CCNP DC
- VCP-DCV and VCAP-DCV
- Some OpenStack Neutron
And on the first three, you can back off one cert level on one, or possibly two, depending on your goals.
Foundational SDN
- Mininet w/ options
- POX w/ options
- Wireshark of it all
- OpenFlow protocol (for learning’s sake)
Basically try as many command-line options as you can with Mininet and POX. Try the options to make POX act like a hub, switch, and router. Understand the resulting OpenFlow flows.
Pick a few more SDN controllers, install, and repeat similar exercises using Mininet.
Mininet lets you easily point to any controller by IP address and port. Try Open Daylight and a vendor’s controller.
Make a choice of Continue reading
Tech Talks: MPLS Traffic Engineering Basics
After covering the basics of MPLS, the discussion I had with Seamus Gilchrist turned to the basics of MPLS Traffic Engineering.
The video of that discussion is available online on the ipSpace.net Tech Talks web page.
Datacenter resource fragmentation
The concept of resource fragmentation is common in the IT world. In the simplest of contexts, resource fragmentation occurs when blocks of capacity (compute, storage, whatever) are allocated, freed, and ultimately re-allocated to create noncontiguous blocks. While the most familiar setting for fragmentation is memory allocation, the phenomenon plays itself out within the datacenter as well.
But what does resource fragmentation look like in the datacenter? And more importantly, what is the remediation?
The impacts of virtualization
Server virtualization does for applications and compute what fragmentation and noncontiguous memory blocks did for storage. By creating virtual machines on servers, each with a customizable resource footprint, the once large contiguous blocks of compute capacity (each server) can be divided into much smaller subdivisions. And as applications take advantage of this architectural compute model, they become more distributed.
The result of this is an application environment where individual components are distributed across multiple devices, effectively occupying a noncontiguous set of compute resources that must be unified via the network. It is not a stretch to say that for server virtualization to deliver against its promise of higher utilization, the network must act as the Great Uniter.
Not just a virtual phenomenon
While Continue reading
Cumulus Linux: First Impressions
Typically, when you buy a network router or switch, it comes bundled with some version of the manufacturer's operating system. Cisco routers come with IOS (or some derivative), Juniper routers come with Junos, and so on. But with the recent proliferation of merchant silicon, there seem to be fewer and fewer differences between competing devices under the hood. For instance, the Juniper QFX3500, the Cisco Nexus 3064, and the Arista 7050S are all powered by an off-the-shelf Broadcom chipset rather than custom ASICs developed in-house. Among such similar hardware platforms, the remaining differentiator is the software.
One company looking to benefit from this trend is Cumulus Networks. Cumulus does not produce or sell hardware, only a network operating system: Cumulus Linux. The Debian-based OS is built to run on whitebox hardware you can purchase from a number of partner Original Device Manufacturers (ODMs). (Their hardware compatability list includes a number of 10GE and 40GE switch models from different vendors.)
Cumulus Linux is, as the name implies, Linux. There is no "front end" CLI as on, for example, Arista platforms. Upon login you are presented with a Bash terminal and all the standard Linux utilities (plus a number of Continue reading
Rome Wasn’t Software Defined In A Day
Everywhere you turn, people are talking about software defined networking. The influence can be felt in every facet of the industry. Major players are trying to come to grips with the shift in power. Small vendors are ramping up around ideas and looking to the future. Professionals are simultaneously excited for change and fearful of upsetting the status quo. But will all of these things happen overnight?
Not Built In A Day, But Laying Bricks Every Hour
The truth of SDN is that it’s going to take some time for all the pieces to fall into place. Take a look at the recent Apple Pay launch. Inside of a week, it has risen to become a very significant part of the mobile payment industry, even if the installed base of users is exclusive to iPhone [6,6+] owners. But did this revolution happen in the span of a couple of days?
Apple Pay works because Apple spent months, if not years, designing the best way to provide transactions from a phone. It leverages TouchID for security, a concept introduced last year. It uses Near Field Communication (NFC) readers, which have been in place for a couple of Continue reading